Question

In nitric acid synthesis, is the catalytic oxidation or absorption stage more likely to explode?

Answer 1

Solution:

In nitric acid synthesis catalytic oxidation is more likely to explode because,

The catalytic reactor is to be designed to give a uniform distribution of the air/ammonia mixture over the catalyst gauzes or pellets. Maintenance of the catalyst operating temperature is very important for the NO (nitrous oxide) yield. This is achieved by adjusting the air/ammonia ratio and ensuring that the lower explosive limit for ammonia in air is not exceeded.

Ammonia is reacted with air on platinum/rhodium alloy catalysts in the oxidation section of nitric acid plants. Nitric oxide and water are formed in this process according to the following reaction:

4NH3 + 5O2 = 4NO + 6H2

Above reaction is exothermic reaction and its heat or enthalpy is used for furthur process.Hence, catalytic oxidation is more likely to explode because if we fail to ensure proper ratio of air/ammonia it will explode ammonia in air and yield of nitrous oxide (NO) get reduces.